Glassdance

 

Photo by Will Gullette

 

1.
Blue Nights, by Cris Forster

 

Brian B. James, Bass Canon
Heidi Forster, Glassdance
Deborah Knapp, Just Keys
Brandis Moylan, Bass Marimba

 

2.
Lullaby, by Cris Forster

 

Heidi Forster, Glassdance

 

Heidi Forster playing Glassdance

Photo by Will Gullette

 

 

Built: ..... 1982–1983, San Diego, California.
Dimensions: ..... Total number of glasses:  48.
Length of stand:  55 ˝ in.
Height of stand:  42 ˝ in.
Width of stand at wheels:  42.0 in.
Overall height of instrument:  76 ˝ in.
Materials: ..... Lead crystal glass, Douglas fir, birch, teak,
mahogany, aluminum, brass, and steel.
Range: ..... Lowest glass:  G above middle C.
Highest glass:  Third G above middle C.

                             

          The Glassdance, which consists of 48 revolving tuned crystal glasses, belongs to a relatively rare family of friction instruments.  It was inspired by Benjamin Franklin’s ‘glass armonica and is by far the most complex instrument I have built to date.  In the detailed graphic, note that the stems of the glasses are mounted through the centers of red sprockets.  A variable speed motor coupled to a modular drive transmission rotates the glasses.  Consequently, a performer may play two or more glasses simultaneously.  This instrument has a remarkable sensitivity to touch, and a rich variety of tones and timbres.  (See also: Creative Aspects > Glassdance Discussion.)